Re: Physics debate
Posted: Thu Jan 19, 2023 3:13 pm
Re: Physics
Einstein couldn't ski for shit!
Einstein couldn't ski for shit!
This is the World Famous TelemarkTalk / TelemarkTips / Telemark Francais Forum, by far the most dynamic telemark and backcountry skiing discussion board on the world wide web since 1998. East, West, North, South, Canada, US or Europe, Backcountry or not.
http://telemarktalk.com/
Agree (and as posted prior) that some systems are free-pivot (like this frame pivot) and others are not as the boot (sole, last) often becomes part of the equation ala a triangle making it operate differently, same as when you add a spring or damper to a screen door. If a heel-band-binding/cable pivots in the same axis as boot flex, it is effectively* "neutral" (* my gut tells me a flexing leather boot forefoot doesn't have a rock-solid pivot point, so a little give is accorded).tkarhu wrote: ↑Thu Jan 19, 2023 2:47 pmA lot of their difference comes from where and how cables are attached. Others have reached same conclusions elsewhere, see citation below. It might have been nothing new to @lowangle al so I do see why this might not have felt relevant. Just old things expressed in an new way.
https://earnyourturns.com/34754/diy-2-p ... orce-luke/Consider 22 Designs Axl and Voile Switchback as examples. The reputation for these two bindings are at opposite ends of the activity spectrum, with the Switchback being a ‘neutral’ cable binding and Axl, the free-pivot descendant of the Hammerhead, the epitome of adjustability and the benchmark of comparison for tele power. […] Resistance to heel lift can be determined with a lil’ trigonometry by splitting the vector representing the spring force of the cable into vertical and horizontal components. Analyzed this way it is easy to see why the Switchback is more neutral than an Axl in position 3 (or 2 or 1).
Comparing the rate of angular increase. For approximately 20° of heel lift, the Switchback cable changes 21°, Axl 25°.
The steeper the angle, the larger the vertical component of force (resistance to heel lift)
otherwise known as activity. (Angles shown are simple examples, not measured values)
Source: https://earnyourturns.com/34754/diy-2-pin-tele-use-the-force-luke/
I think the only one who can answer that may have left the room.
Does anyone see the cable changing length here?GrimSurfer wrote: ↑Wed Jan 18, 2023 1:23 pmIt’s about the cable. It has always been about the cable. I’ve focused on the NN 3 pin 75mm binding because of two things:
1. That’s what started the discussion, so it makes sense to stick to the to the topic for the purposes of consistency; and
2. How the cable interacts with the NN 3 pin 75 mm binding (which is fixed to the ski and has no moving parts other than the bale).
This topic has always been about the NN 3 pin 75 mm binding. People might not like that because it avoids the issue of how these bindings work differently than some may have thought.
I'm just saying I do not "see" any in the gif, nor TomT's video on full screen. And "spring ... is compressed" is ambiguous as for the same direction of movement a spring can be Compressed OR Stretched depending on design.
Agree, this instance may have little to no downward from the cable, or the boot is too soft in relation to spring force. Cables on my leather boots didn't crush (binding photos earlier in thread) and there was progressively more resistance with flex, clearly more so than my Rota' 3-pins.
More or less, I concur.
Then the deaf man wrote, "Five hundred posts is a good stopping point for a thread, no?"A group of six blind men heard that a strange animal, called an "el-e-phant," had been brought to the town which none of them knew about. So they sought it out, and its handler began guiding them over to it.
"An elephant is like a thick snake!" said the first, whose hand landed on the trunk.
"No, it is like a fan," said another whose hand reached its ear.
"More like a tree trunk," said the one whose hand was upon its leg.
"How can you confuse a wall for that?" said the blind man who was feeling the elephant's side.
"Or a rope for a wall?" said the fifth who happened upon the tail.
The last let out a gasp of surprise when he encountered the tusk, saying, "All your joking trying to mislead me, nearly let me get impaled by this spear-like creature!"